Tool assemblies deployed into a wellbore of a well system (e.g., oil or gas wells for extracting fluids from a subterranean formation) may include multiple components or devices coupled together. Several of such tool assemblies require movement or actuation of specific mechanical parts, and may further require or be optimized by, locking such mechanical parts in a specific position. The movement of mechanical parts within tool assemblies can be subject to, and in some conditions primarily controlled by, the annulus pressure within the wellbore. Such locking of parts or tool assemblies during deployment may be advantageous as the tool assemblies are moved uphole or downhole within a well system and wellbore. Accordingly, there remains a need for actuating mechanical aspects of tool assemblies during deployment in a wellbore without the complexity of controlling such parts at pressures other than the wellbore environment annulus pressure.